钢筋混凝土桥梁单墩体系目标位移计算方法研究

Research on Calculation Method of Target Displacement in Single Column Systems of Reinforced Concrete Bridges

对钢筋混凝土桥梁单墩体系目标位移的确定方法进行了总结,对基于材料应变的目标位移确定方法进行研究,单墩体系目标位移的确定取决于截面受压区高度和等效屈服曲率的计算,应用截面分析软件UC-Fy-ber对大量方形及圆形截面进行弯矩—曲率分析,得到2种截面的受压区高度随结构设计参数变化的计算式,拟合得到与研究数据符合较好的等效屈服曲率计算式,在此基础上得到了单墩体系目标位移随结构设计参数变化的计算式,提出了单墩体系目标位移的实用计算方法,分析了截面形式、混凝土强度等级、纵筋配筋率、截面尺寸、混凝土压应变和结构高度等设计参数对单墩体系目标位移取值的影响,最后由参数分析的结果提出了增大单墩体系目标位移的具体措施。

The calculation method of target displacement in single column systems was summarized. Study on the material strain-based method indicated that the calculation of target displacement depended on the under pressure district height and the equivalent yield curvature of the cross-section. Section analysis software UC-Fyber was used to analyze the moment-curvature performance of square sections and circular sections. The calculation formula of the under pressure district height was educed, also equivalent yield curvature formula that accord well with the research data was educed. The formula of material strain-based target displacement was put forward that can applied to the two different section forms. Practical calculation method of target displacement was educed. Influence analysis of the section form, concrete strength grade, longitudinal reinforcement ratio, section size, and concrete pressure strain and structure height to the target displacement value was done. Measures to increase target displacement are suggested by the influence analysis result.